Assembling and Arrangement Flat Element Consisting of One or Several Elements

ABSTRACT

The assembling element defining a plane comprises primary and secondary structures which are positioned substantially in parallel to the plane. The primary structure comprises at least two separate beams each of which is provided with boards having a rectangular cross-section, parallel with respect to each other and placed on an edge along the longitudinal axis thereof parallel to the plane of the building element. One or several boards are laterally offset in a perpendicular direction to the plane and at least two boards are not laterally offset. The secondary structure connects the separate beams to each other by the internal edges of at least two boards which are not laterally offset.

The present invention relates to a flat assembling element. The invention also relates to an assembling arrangement that is formed from one or more flat assembling elements.

In the construction industry, in the widest sense of the term, timber is increasingly being used to build various structures. Advances in transformation and prefabrication processes as well as the benefits of using timber in terms of sustainable development objectives mean that construction projects that use timber have a particular advantage. Timber is also associated with other materials such as concrete, polymer materials, metals, glass and other materials.

However, industrially developed high-performance architectures and arrangements must:

-   -   be prefabricated in order to reduce on-site assembly times,     -   be multifunctional in order to obtain savings in terms of the         number of layers required and allow use for interior or exterior         architectures,     -   have mechanical characteristics that are perfectly controlled in         terms of fire resistance, acoustics and as far as subsequent         uses are concerned (for the insertion of other elements such as         service shafts, etc.),     -   use an ecologically and economically soundly based material such         as a solid wooden board,     -   be easy to dismantle, if necessary, for example in the context         of temporary structures, in order to take into account         ecological constraints requiring reuse of materials that are         used in such a context, and     -   be highly competitive in terms of price.

By way of example, the field of floor slabs is experiencing rapid change based on the use of seasoned solid planks in an all-timber system or mixed system with timber associated with linked concrete in order to achieve long spans.

DESCRIPTION OF THE PRIOR ART

Arrangements having large dimensions such as horizontal floor slabs, suspended platforms or platforms mounted on piles and vertical walls capable of supporting large fixed or moving loads have already been implemented in this way.

Document DE-1.609.888 describes a floor structure comprising a primary structure made of longitudinal parallel boards, at both ends of which several battens are located in order to create an I-shaped profile. The longitudinal boards form a central web that makes up the thickness of the floor and gives it inertia and have compressive and tensile reinforcement in the form of one or a plurality of battens that are symmetrical on the upper part and the lower part. A floor structure secured by secondary joists is placed on the boards.

Document PL-170.890 describes a structure made of parallel boards that are laterally secured by counter-braces. A horizontal board intended to support an upper lay of concrete is placed between two parallel boards.

Document EP-1.323.876 discloses a caisson made of two substantially parallel boards connected by longitudinal counter-braces. The counter-braces are inserted in an upper longitudinal batten for compression forces provided at the level of the upper plate and in a lower longitudinal batten for tensile forces provided at the level of the lower plate.

Document WO-02/31.283 discloses a prefabricated floor element consisting of a caisson that includes an upper cross-band panel that is used as a compression cover. The upper panel is placed on several central boards, the base of which includes one or two offset battens. These central boards act as a spacer in order to give the caisson inertia.

This system is merely a simple prefabricated caisson and does not allow any version other than the described caisson with boards and a panel. The central board with its batten(s) does not form a beam. In fact, without the upper panel that must be rigidly connected, the performance of the caisson is substantially equal to the inertia of the central boards. The two lateral battens do not reinforce the actual beam. The panel must even be notched in order to properly fit the tip of the board and in order to form an indissociable whole.

Document DE-195.37.298 describes an arrangement made of wood consisting of a succession of parallel boards arranged vertically and being alternatively slightly offset in the vertical plane in order to build self-supporting roofing panels. At the same time, these panels constitute the internal frameworks of the space located underneath the roof. However, the loads applied must be evenly distributed and the spans obtained remain small and of the order of 3 m to 5 m.

In order to achieve longer spans, Document FR-2.777.112 discloses an association of a layer of concrete poured over boards arranged vertically and slightly offset in the vertical plane in order to be able to accommodate a transverse fastener that immobilises the concrete on the wood. With this arrangement, spans of 7 m to 8 m are possible for standard floor slab loads equal to 300 kg/m².

For instance, in order to achieve long spans with solid boards placed on edge, Document EP-1.149.213 discloses parallel boards placed on edge with a distance between offset boards up to the technical limits of the composite section. The thickness obtained for the arrangement makes it possible to significantly increase the clear span without requiring any intermediate support. An upper panel is used to stabilise the boards against buckling and constitutes the floor of the upper story.

However, the major limitation of these arrangements is the fact that, for a given surface area, they involve using extremely large quantities of timber to obtain relatively limited spans of 5 m to 9 m. The large quantity of timber required makes the arrangement and the entire structure heavier.

In addition, when these arrangements are used as a floor slab, they make it impossible to incorporate the usual shafts and ducts of a building (air flow system, ducts for ventilation, air conditioning and electricity, etc.). Also, when these arrangements made of solid seasoned boards are used and if heavy rain dampens the timber, the panels made of boards swell like a sponge. This phenomenon causes major problems in the building either by exerting thrust against the walls or by bending upwards in the same shape as a roof tile in order to absorb transverse expansion.

SUMMARY OF THE INVENTION

One main problem that the invention aims to solve is to perfect an assembling element capable of forming an arrangement of the horizontal floor slab or vertical wall type that is both simple and economical in terms of the quantity of boards required. The second problem is to produce an element that, by virtue of its design, makes it possible to have clearances or voids in order to insert the shafts, pipes and wiring of a building. The third problem is to devise a flat element made of wood that has a satisfactory ability to absorb mechanical deformation. The fourth problem is to obtain a 2 or 3 dimensional arrangement that integrates one or more flat elements.

In a known manner, an assembling element that defines a plane comprises primary and secondary structures which are positioned substantially in parallel to the plane.

According to the invention, the assembling element is characterised:

-   -   in that the primary structure has at least two separate beams,         each of which is provided with boards having a rectangular         cross-section, parallel with respect to each other and placed on         an edge along the longitudinal axis therefore parallel to the         plane of the building element wherein,     -   one or several boards are laterally offset in a perpendicular         direction to the plane, and     -   at least two boards are not laterally offset; and     -   in that the secondary structure connects the separate beams to         each other by the internal edges of at least two boards which         are not laterally offset.

In other words, a separate beam, formed from at least two offset boards, constitutes a high-performance primary structure. These beams, given the special layout of their boards, are concentrated structural elements. The boards of each beam are laterally offset, i.e. relative to their width. Also, if the boards happen to swell because of humidity at the construction site, this is no longer a problem because the entire gap on each side is available to allow expansion.

The association of the beams with the secondary structure constitutes the flat element. The presence of the secondary structure above all the beams made of boards makes it possible to absorb the mechanical stresses exerted on the element thus formed.

The flat element may comprise a plate capable of being secured by the two opposite-facing boards each located on the edge of each of the separate adjacent beams. The plate may be freely located at various levels. The plate, the boards and the secondary structure delimit an enclosed space that constitutes a caisson. These plates have an architectural function, for example for rendering the ceiling and sometimes have a technical function in terms of acoustics or fire resistance.

The interior is understood to be the side that faces the boards that are not offset or faces the secondary structure. The exterior is understood to be the side that faces the boards that are offset relative to the general plane of the element or is opposite the secondary structure.

In a first embodiment, the element may comprise a plate for joining two separate adjacent beams fixed on an internal edge of two opposite-facing laterally offset boards each located on the edge of each of the separate adjacent beams. In another embodiment, the element may comprise a plate for joining two separate adjacent beams fixed on the external edge of opposite-facing boards that are not laterally offset, each located on the edge of each of the separate adjacent beams. In yet another embodiment, the element may comprise a plate for joining two separate adjacent beams fixed on the external edge of opposite-facing laterally offset boards each located on the edge of each of the separate adjacent beams. In a final embodiment, the element may comprise a plate for joining two separate adjacent beams fixed on an internal edge of two opposite-facing boards that are not laterally offset, each located on the edge of each of the separate adjacent beams.

The assembling element may comprise a part for joining two separate adjacent beams capable of being fixed on the exposed surface of two opposite-facing laterally offset boards. This connecting part may be formed by an alternating sequence of boards and spacers that are laterally offset at right angles to the plane. These boards and spacers give the connecting part a crenellated appearance that is substantially similar to the appearance of the beams with an alternating sequence of offset board and non-offset board.

The assembling element may also comprise a part for connecting two separate adjacent beams fixed on the exposed surface of two opposite-facing boards that are not laterally offset. This connecting piece may be formed from boards that are laterally offset at right angles to the plane and positioned at various heights like a staircase. These offset boards give the connecting piece a crenellated staircase-like appearance.

Advantageously, the beams may comprise an upper strip that is fixed on the internal edge of the boards that are not laterally offset. In another advantageous layout, the beams may comprise a localised concrete layer with a precise layout which is poured by filling the gaps delimited by the boards that are not laterally offset and the internal edge of the boards that are laterally offset.

In one particular preferred layout, the beams may comprise a regular alternating sequence of laterally offset boards and boards that are not laterally offset. To achieve excellent mechanical strength, each of the beams may comprise an odd number of boards.

Preferably, the secondary structure may be a load distribution panel or a series of battens or other items fixed on the internal edge of the boards that are not laterally offset or on the localised layer of concrete or on the upper strip. This secondary structure element, for example for a floor, which is made of panels or beams or wooden square cross section blocks or battens must be continuous over the primary beams so as not to introduce any twisting of the main beams when a concentrated local load is applied between two beams.

The secondary structure may also preferably be a layer of concrete poured over the plate and covering the separate beams. In this way, this high-performance beam made up of several base boards can be reinforced by a layer of linked concrete located in the upper part in order to reinforce the compression area.

The assembling element may favourably comprise several fasteners inserted into each separate beam perpendicular to the longitudinal axis of the boards. In this case, the connection making it possible to attach the two materials, wood associated with concrete, is a transverse wooden or metal fastener. The boards may be alternatively offset by a distance of 30% to 200% relative to the dimension of the area where these boards cross over.

The separate beams may join each other so as to obtain an aesthetic appearance of the element and the arrangement or they may have a 3-dimensional configuration. Thus, the plates may have a substantially triangular, lozenge or quadrilateral shape.

According to a second aspect of the invention, an arrangement is formed using one or more elements as described above and is characterised in that it constitutes a floor, a ceiling, a truss, a noise wall, elements forming partitions, walls or dividers, floor slabs, flat or single or double pitched roofs, bridge platforms, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the present invention and its various advantages and features may more readily be understood, the following description is given, merely by way of example, reference being made to the accompanying drawings:

FIG. 1 is a perspective bottom view of an assembling element in accordance with a first embodiment;

FIG. 2 is a side view of the assembly element in FIG. 1;

FIG. 3 is a cutaway perspective top view of an assembling element according to a second embodiment;

FIG. 4 is a cutaway perspective top view of an assembling element according to a third embodiment;

FIG. 5 is a side view of the assembling element in FIG. 4;

FIG. 6 is a bottom perspective view of an assembling element according to a fourth embodiment;

FIG. 7 is a lateral cross-sectional view of an assembling element according to a fifth embodiment;

FIGS. 8 to 11 are cutaway perspective top views of an assembling element according to the sixth, seventh, eighth and ninth embodiment respectively;

FIG. 12 is a cross-sectional view of an assembling element according to a tenth embodiment;

FIG. 13 is a cross-sectional side view of an assembling element according to an eleventh embodiment;

FIG. 14 is a cross-sectional side view of an assembling element according to a twelfth embodiment;

FIG. 15 is a top view of a ceiling type arrangement formed from assembly elements;

FIG. 16 is a partial perspective view of a truss-type arrangement formed from assembling elements; and

FIG. 17 is a side view of an anti-noise arrangement formed from assembling elements.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIGS. 1 and 2 and in a first embodiment of the invention, assembling element (1) has a general plane (P) that is substantially horizontal in this case. Assembling element (1) comprises several primary structures or beams (2) consisting of five boards (3) that are screw fastened together. Boards (3) have a rectangular cross section. Boards (3) are assembled parallel to each other. Boards (3) are arranged on edge. The longitudinal axis (L) of boards (3) is parallel to the plane (P) of assembling element (1).

Of these five boards (3), one board out of two is alternatively laterally offset, i.e. relative to the width of board (3), relative to each other at right angles to the plane (P) of element (1). Thus three boards (4) are downwardly offset and two boards (6) are not offset. The three offset boards (4) grip the two boards that are not offset (6) in an overlap area (5).

A beam (2) is prefabricated by using fasteners, screws or nails or pins, metal or wood, or by bonding. Very generally speaking, screws are preferred to other types of fasteners. Beam (2) consists of an odd number of boards (3), of five to seven boards (3) or more, i.e. N boards (4) arranged on edge and screw fastened and offset as much as possible and N−1 boards that are not offset (6) or N+1 boards that are not offset. The offset between boards (4 and 6) is 30% to 200% offset relative to contact and overlap area (5) between boards that are offset and boards that are not offset (4 and 6) which accommodates the fasteners.

The basic materials for building the beams (2) are solid boards, laminated boards (double or triple layer or reconstituted solid wood), glued-laminated wood or Laminated Veneer Lumber (LVL) panels or plywood or also panels called OSB® (Oriented Strand Board) or any other type of beams based on timber or timber derivatives or reconstituted timber and other materials. It should be noted that these beams (2) can be completely prefabricated at the factory in order to ensure greater quality, construction under dry conditions and extremely fast on-site builds.

A plate (7) or ceiling panel is placed and fixed on internal edge (8) of offset board (4) located at the edge of beam (2) and therefore facing the corresponding offset board (4) located on the edge of corresponding adjacent beam (2). Construction of a flat element (1) is obtained using previous beams (2) which occupy roughly 10% to 50% of the surface area and alternate with the non-structural areas of plates (7).

Plates (7) delimit a caisson through which shafts and other tubes can pass. This element (1) constitutes a “high ceiling” that reveals the beams that constitute it (2). Plates (7) provide the internal finishing for the lower space. Traditional plywood panels can be used for these plates, ceiling panels or cladding (7). Panels made of synthetic or rigid insulating materials (e.g. rock wool) can be used to act as a sound absorber or even cutaway lathing panels to achieve architectural appearances and ensure permeability of the ceiling (flow of warm air, ventilation, loudspeaker, in commercial environment, etc.). To ensure fire resistance, these plates (7) can be selected from a non-flammable material (class MO) or flame resistant material (class Ml).

According to the invention, a secondary structure consisting of an upper floor panel or a load distribution panel (9) is placed on the internal edges (11) of the boards that are not offset (6). The continuity of this panel (9) allows virtually uniform loading of the various upper boards that are not offset (6) of beam (2). In such a case, load distribution panel (9) associated with element (1) preferably consists of a wooden panel, preferably of the cross-veneer laminated type, has a strong axis in the direction of its fibres and weak axis in the direction of two or three cross plies. This panel (9) is screw fastened on separate beams (2) ensuring continuity over said beams (2).

It must be emphasised that secondary structure floor panel (9) is sized so as to be able to support this distributed or concentrated load when it is applied between the two primary beams (2). All the variations described below offer the same performance with, for example, 50/200 mm boards offset by 120 mm, a beam ratio of 30% (⅓). Flat element (1) obtained has a load bearing capacity of 6 m to 8 m for a load of 300 kg/m².

In a second embodiment of the invention (see FIG. 3), the same solution as that of the first embodiment (1) is chosen for element (12) with beams (2), the three offset boards (4) and two boards that are not offset (6) which constitute them and the interposed plates (7). The upper floor panel (9) is supplemented by a sound absorber (13) placed on floor panel (9) then a finishing layer (14) that constitutes the finished floor of the upper space.

In a third embodiment of the invention (see FIGS. 4 and 5), element (16) comprises beams (2) in a way that is substantially similar to that of the first and second embodiment (1 and 12). However, the alternate sequence of component boards (3) is reversed. Three boards that are not offset (17) secure two offset boards (18). Load distribution panel (9) is placed on internal edges (11) of the boards that are not offset (6).

The ceiling caisson is made using a plate (19) suspended at the bottom on the external edge (21) of the upper lateral board that is not offset (17) of beam (2). In this embodiment (16), beam (2) remains proud relative to caisson plate (19). Two mounting solutions are preferred, using the clip described in Document EP-1.000.207 which enables concealed fixing or using a triangular batten (22) that acts as a trim for the fastener and which shows a small cornice in the exposed ceiling. Obviously, other customary fixings are also possible.

In a fourth embodiment of the invention (see FIG. 6), element (23) is reminiscent of the first and second embodiments (1 and 12). Beams (2) comprise two boards that are not offset (6) and three offset boards (4). The load distribution panel secondary structure (9) is placed on the internal edges (11) of the boards that are not offset (6).

Plate (24) is suspended at the lower level on the external edge (26) of an additional laterally offset lower board (27) that is placed alongside the offset boards (4) on the edge of beam (2). This has the effect of concealing the height of beam (2) and therefore produces a flatter ceiling. Other solutions can be adopted in order to attach plate (24). Rabbets or grooves can be made in the board. Rails, brackets or clips can be separately mounted.

In a fifth embodiment of the invention (see FIG. 7), one element (28) comprises three boards that are not offset (29) and four downwardly offset boards (31). Notches or rabbets (32) are made in the area where the boards that are not offset (29) and four downwardly offset boards (31) overlap. These rabbets (32) make it possible to reduce the gap (33) between the boards that are not offset (29) and between the downwardly offset boards (31).

In a similar manner to the first embodiment (1), a plate (7) is mounted on internal edge (8) of the boards that are offset (31) on the edge of beam (2).

For each beam (2), a localised internal strip (34) is fixed on internal edge (11) of the boards that are not offset (29). The width of this internal strip (34) substantially equals the width of beam (2) with its edge extending roughly vertically above offset board (31) located on the edge. Strip (34) has its strong axis parallel to axis (L) of boards (3) of these beams (2). This provides a π-shaped beam (2). Load distribution panel (9) is placed directly onto internal strips (34).

In a sixth embodiment of the invention (see FIG. 8), one element (36) is reminiscent of element (23) in the fourth embodiment with beams (2) comprising two boards that are not offset (6), three offset boards (4) and plate (24) suspended on the external edge of additional offset board (27). An additional plate (37) is placed on the internal edges of offset boards (4 and 27) at the edge of beams (2).

A layer of concrete (38) is poured on plates (29) and over the totality of element (36) so as to cover beams (2) at the level of the boards that are not offset (6). Concrete (38) forms the secondary structure and reinforces the compressed upper area. Load distribution panel (9) is placed on concrete (38) to ensure finishing. Concrete (38) is appropriate to the required performance level. The concrete of choice is a high-performance, lightweight concrete containing wood or synthetic aggregates or any other traditional concrete.

In a seventh embodiment of the invention (see FIG. 9), one element (39) is substantially similar to element (36) in the fifth embodiment. Concrete (38) is connected to the timber by means of a transverse fastener (41), for example one having substantially the same width as beam (2). Load distribution panel (9) is placed on concrete (38). Finally, an additional finishing or floor treatment layer (42) is provided on load distribution panel (9).

In an eighth embodiment of the invention (see FIG. 10), element (43) with beams (2) has four boards that are not offset (44) and five offset boards (46). A concrete skim or localised layer (47) is poured on the internal edge of the boards that are not offset (44). This localised layer (47) penetrates the three spaces delimited by the internal edge of offset boards (46) and the boards that are not offset (44). Localised layer (47) stops substantially in the middle of the edge of the board that is not offset (44) on the edge of beam (2).

A plate (48) is then mounted on this internal edge of the board that is not offset (44) at the edge. Plate (48) is used as formwork for screed (49) poured on localised layer (47) and between beams (2) forming a continuous surface. This screed (49) may or may not comprise reinforcement (51). A second ceiling can be freely arranged in order to box in the area between two beams (2) and conceal building technical services.

The finishing coat may remain the concrete screed (49), for example for a tiled finish or for installing an underfloor heating system. It should be noted that screed (49) is then part of the secondary structure of the floor. Concrete (49) does not reinforce the load-bearing capacity of basic beam (2) because concrete (49) is not connected to beam (2). In fact, it floats on the secondary panel formed by plates (48).

In a ninth embodiment of the invention (see FIG. 11), one element (52) comprises the same beams (2) as those in the eighth embodiment (43). Localised layers of concrete (47) are poured on the edge of the boards that are not offset (44). This localised layer (43) penetrates into the three spaces left by offset boards (46) between the boards that are not offset (44). Localised layer (46) stops substantially at the edge of the board that is not offset (44) at the edge of beam (2). A continuous lower panel (53) is fixed on the external edge of offset boards (46). This lower panel (53) completely covers and conceals beams (2).

A secondary structure made of continuous tesserae (48) is fitted on beams (2). These tesserae (54) have a resilient sound absorber placed underneath their support on beam (2) and then accommodate a panel (9) or a traditional floor or even known solutions according to the current state of the art. This solution may be appropriate in certain industrial settings in order to make the ceiling panel more economical. The space between two load-carrying beams (2) is therefore not boxed in.

In a tenth embodiment of the invention (see FIG. 12), one element (56) has beams (2) with three boards that are not offset (29) and four offset boards (31) as in the fifth embodiment (28). The boards that are not offset (29) have notches (32) in the area where they overlap in order to allow their adjustment with the offset boards (31) that grip them.

As in the first embodiment (1), a plate (7) is mounted on internal edge (8) of offset boards (52) at the edge of beam (2). For each beam (2), a strip (34) is fixed on internal edge (11) of the boards that are not offset (29). The width of this strip (34) is substantially equal to the width of beam (2) with its edge roughly extending vertically above offset board (31) at the edge.

A layer of concrete (57) is poured on plates (7) and strips (34) so as to cover beams (2) and part of the space left between the latter. Acoustic film (58) is placed on concrete (57) and linoleum (61) or an equivalent floor covering or other materials ensure finishing.

In an eleventh embodiment of the invention (see FIG. 13), one element (62) has beams (2) with four boards that are not offset (6) and five offset boards (4) as in the eighth (43) and ninth embodiments (52). A secondary structure comprises, from the internal edge of the boards that are not offset (6) the following items respectively: a KERTO S panel (63), for example 27 mm thick, a resilient sound absorber (64), for example 15 mm thick, and a concrete top screed (66), for example 50 mm thick.

Connecting pieces (67) are provided in order to ensure continuity between two beams (2). To fix connecting pieces (67), the visible surface of the two opposite-facing offset boards (4) of two contiguous beams (2) has notches. These connecting pieces (67) comprise an alternating sequence of offset boards (68) and spacers that are also offset (69). The internal edges of offset boards (68) and of offset spacers (69) are all at the same level. The external edges of offset boards (68) are all at the same level and the external edges of offset spacers (69) are all at the same level but this level is different to that of the external edges of offset boards (68).

Only the position of the external edges of offset boards (68) and of the external edges of offset spacers (69) varies depending on the height. Only the width and thus the exposed height of offset boards (68) relative to the width and thus the exposed height of offset spacers (69) varies alternately. These connecting pieces (67) ensure crenellated continuity of the external edges of offset boards (4) and of the boards that are not offset (6) that constitute beams (2).

In a twelfth embodiment of the invention (see FIG. 14), one element (71) has beams (2) with four boards that are not offset (6) and five offset boards (4) as in the eighth (43), ninth (52) and eleventh (62) embodiments. A secondary structure comprises, from the internal edge of the boards that are not offset (6) the following items respectively: an OSB board (63), for example 10 mm thick, a resilient sound absorber (64), for example 15 mm thick, and a top concrete screed (66), for example 60 mm thick.

Connecting pieces (72) are provided in order to ensure continuity between two beams (2). These connecting pieces (72) comprise an alternating sequence of offset boards (73). These offset boards (73) are placed at different heights, staircase fashion. The internal and external edges of offset boards (73) are not all at the same level but are evenly offset at right angles to plane (P). Offset boards (73) of connecting piece (72) will touch the wooden panel (63) of the secondary structure.

These offset boards (73) give connecting piece (72) a crenellated, staircase-like appearance. In order to accentuate this staircase look, offset boards (4) that constitute the beams have different widths. This therefore gives a sine-wave shape with the offset boards (4) of beams (2) and the offset boards (73) of connecting pieces (72).

In FIG. 15, a first arrangement (74) is formed using several flat elements. This first arrangement (74) is more elaborate and no longer has beams with bases that are parallel to each other but a grid of beams (76) extending in the X-Y plane.

A primary wooden beam (77) accommodates other secondary beams (78), for example also similar to beams (2) of the invention, then tertiary beams (79). Finally, the additional floor and ceiling structures are used for finishing but with plates (81) having a much greater variety of geometrical shapes such as triangles, lozenges and other quadrilateral shapes. This solution makes it possible to produce an ornate ceiling in the lower space.

In FIG. 16, a second arrangement (82) is formed using several flat elements with wooden beams (2). This is an exposed frame with an attic space. The same finish is obtained with a secondary ceiling panel (83) and a panel or upper secondary battens that are used as roof boarding (not shown).

In the case of this frame, the flat elements assembled in three dimensions have become a truss with separate beams (2) with offset boards constituting the principal rafters and beams used as a tie-beam (84) in order to reinforce the A-shaped truss.

In FIG. 17, a third arrangement (86) is used as a noise screen. A flat element (87) is substantially reminiscent of the eighth (43), ninth (52), eleventh (62) and twelfth (71) embodiments with four boards that are not offset and five offset boards. Flat element (87) is installed vertically and is attached to a support (88), for example a wall. Boards (3) are therefore oriented in the direction of the area of source(s) from which the sound waves (0) originate and travel towards the front of arrangement (86).

The preceding descriptions demonstrate that the assembling element in accordance with the invention has numerous advantages, especially:

-   -   supports integration of building services, for example lighting         can be incorporated in the ceiling caisson, lagging can be         installed in all or part of the caisson and sound insulation can         be fitted in order to deaden the noise of impact on the floor;     -   good resistance to bending by combining beams made of offset         boards and a secondary structure with economy of materials         thanks to the use of panels or concrete and the spacing between         the beams that constitute it; and     -   allows total dismantling of the assembled-board structure if the         arrangement or the building needs to be removed and this allows         reuse of the boards that constitute it or recycling in a         different industry (formwork, packaging, beam made of boards,         etc.)

The present invention is not confined to the embodiments described and illustrated. Numerous modifications can be made without extending beyond the scope defined by the set of claims.

The embodiments can be combined with each other in order to obtain multiple appearances of the finished arrangement. The number of boards that constitutes the beams is not limitative. There are many applications using horizontal or vertical beams with elements forming partitions or dividers, flat roofs or single or double pitched roofs, bridge platforms, etc. 

1. Assembling element defining a plane comprising a primary structure and a secondary structure which are substantially parallel to the plane, wherein the primary structure has at least two separate beams each of which is provided with boards having a rectangular cross-section with an internal edge and an external edge, the boards of rectangular cross-section being parallel to each other and placed on an edge along a longitudinal axis of the boards with their internal edge and external edge parallel to the plane of the assembling element, one or several of said boards of rectangular cross-section being offset with their internal edge and external edge perpendicular to the plane, and at least two of said boards with a rectangular cross-section not being offset; and the secondary structure connects the separate beams to each other by the internal edges of at least two of said boards with a rectangular-cross section that are not laterally offset.
 2. Element as claimed in claim 1, further comprising a plate for connecting two separate adjacent beams, the plate being fixed on an internal edge of two opposite-facing laterally offset boards, each of the two opposite-facing laterally offset boards being located on an edge of each of the separate adjacent beams.
 3. Element as claimed in claim 1, further comprising a plate for connecting two separate adjacent beams, the plate being fixed on an external edge of opposite-facing boards that are not laterally offset, each of the opposite-facing boards being located on an edge of each of the separate adjacent beams.
 4. Element as claimed in claim 1, further comprising a plate for connecting two separate adjacent beams, the plate being fixed on an external edge of opposite-facing laterally offset boards, each of the opposite-facing laterally offset boards being located on an edge of each of the separate adjacent beams.
 5. Element as claimed in claim 1, further comprising a plate for connecting two separate adjacent beams, the plate being fixed on the internal edge of two opposite-facing boards that are not laterally offset, each of the two opposite-facing boards that are not laterally offset being located on an edge of each of the separate adjacent beams.
 6. Element as claimed in claim 1, further comprising a piece for connecting two separate adjacent beams, the piece being fixed on an exposed surface of two opposite-facing laterally offset boards formed from an alternating sequence of boards and spacers that are laterally offset at right angles to the plane.
 7. Element as claimed in claim 1, further comprising a piece for connecting two separate adjacent beams, the piece being fixed on an exposed surface of two opposite-facing boards that are not laterally offset and being formed by boards that are laterally offset at right angles to the plane and positioned at different heights like a staircase.
 8. Element as claimed in claim 1, wherein the beams comprise an upper strip fixed on internal edge of boards that are not laterally offset.
 9. Element as claimed in claim 1, wherein the beams comprise a localised layer of concrete poured to fill spaces delimited by the boards that are not laterally offset and the internal edge of laterally offset boards.
 10. Element as claimed in claim 1, wherein the beams comprise an alternating sequence of laterally offset boards and boards that are not laterally offset.
 11. Element as claimed in claim 1, wherein the secondary structure is a load distribution panel or a series of battens fixed on internal edge of the boards that are not laterally offset or on a localised layer of concrete or on an upper strip.
 12. Element as claimed in claim 1, wherein the secondary structure is a layer of concrete poured on a plate and covering separate beams.
 13. Element as claimed in claim 1, further comprising several fasteners inserted into each separate beam at right angles to the longitudinal axis of the boards.
 14. Element as claimed in claim 1, wherein the boards are alternately offset by a distance of substantially 30% and 200% compared with a dimension of the area in which said boards overlap.
 15. Element as claimed in claim 1, wherein separate beams join each other with plates have a substantially triangular, lozenge or quadrilateral shape.
 16. Arrangement formed from one or more elements as claimed in claim 1, that constitutes a floor, ceiling, truss, noise wall, elements forming partitions, walls or dividers, floor slabs, flat roofs or single or double pitched roofs or bridge platforms. 